Overall Summary for Padi Huma Bakilong

The padi huma bakilong mini project was carried out over a period of four weeks, from 21 April 2017 to 22 May 2017. The goal of the mini project was to understand the effects of different factors that affect plant growth.
Five different soils samples were used for the mini project, taken from various locations. The soil samples were labeled as S1, S2, S3, S4, and S5 respectively.

Table 1: Locations Where the Soil Samples were Collected

S1	Kg. Pulau Penampang, Menggatal
S2	Outdoor Development Centre (ODEC), Universiti Malaysia Sabah (UMS)
S3	Residential College E, UMS (Café area)
S4	Residential College E, UMS (B1 area)
S5	Mengkabong Lagoon, Tuaran

Each soil sample was first tested for its texture and pH. These two factors are important to know as they affect soil fertility in various ways.

Table 2: Soil Sample and its Soil Texture and pH.

Soil Sample	Soil texture	pH (Universal indicator)	pH (pH Meter)
S1	Clay	5	6.15
S2	Sand	6	6.76
S3	Sandy Clay Loam	3	3.06
S4	Loam	6	6.39
S5	Sandy Loam	5	5.33

As seen in Table 2, S3 was the most acidic of the soils, while S2 and S4 is close to neutral pH. Knowing the soil pH is important as certain plant nutrients are only available in abundance in a certain range of pH such as phosphorus, sulphate, and nitrate which are available mostly within the pH range of 6.0 to 7.5. Comparing Table 2 with Table 3, it can be seen that the soil pH affects the nutrient content. In soil samples S2 and S4 which have slightly acidic soils and is within the nutrient availability range of phosphorus, sulphate, and nitrate, the amount of these nutrients in the soil is relatively high compared to the others. S3, with is high acidity, has relatively lower phosphorus ad nitrate contents while sulphate was out of range of detection. S5, with its pH of 5 has a lower nitrate content compared to S2 and S4, though the phosphorus content is higher compared to the other two. Interestingly, S1 has the lowest nitrate and phosphorus content out of the soil samples despite being the same pH as S2 and S4 according to the universal indicator. However, the clayey soil texture of S1 explains why the phosphorus and nitrate content is low, as these two nutrients tend to leech out from clayey soils. As for the high sulphate readings of S1, the Cation Exchange Capacity (CEC) that increases in clayey soils may have something to do with it, but no further investigations were done in this part.

Table 3: Phosphorus, Sulphate, and Nitrate Content of the Soil Samples

Soil Type, S	Test, T	Nutrient (mg/L)
		Phosphorus	Sulphate	Nitrate
S1	T1	0.76	128	1.20
	T2	0.77	128	1.20
	T3	0.77	128	1.20
Mean		0.77	128	1.20
S2	T1	1.99	27	5.60
	T2	2.00	26	5.60
	T3	2.01	26	5.50
Mean		2.00	26.33	5.57
S3	T1	1.36	-	1.6
	T2	1.37	-	1.7
	T3	1.35	-	1.6
Mean		1.36	-	1.63
S4	T1	1.9	53	10.7
	T2	1.89	52	10.8
	T3	1.86	52	10.8
Mean		1.88	52.33	10.77
S5	T1	2.19	-	4.1
	T2	2.20	-	4.1
	T3	2.19	-	4.1
Mean		2.19	-	4.1

“-“ means out of detection

The soil texture of the soils samples affects the water holding capacity of the soil. Due to the sizes of different soil particles, the water holding capacity varies between different soil textures; sandy soils has the weakest water holding capacity, clay the strongest, with loam in the middle of the two. Water is vital for a plant's survival as well as it is required for seeds to germinate. Table 4 shows the moisture content of the soils after two weeks of drying. S1 has the highest moisture content, since clayey soils have the highest water holding capacity, with S2 having the lowest since the inverse is true for sandy soils. Please note that high water holding capacity does not directly result in fertile soils as clayey soils have poor aeration and sandy soils can produce fertile plants provided plant nutrients are abundant and it is regularly watered. The results of the mini project shows something similar.

Table 4: Moisture Content of Soil Samples After Two Weeks

No. of Sample	Weight of empty bowl (W1)	Weight of bowl + sample (W2)	Weight of bowl + sample after drying for 2 weeks (W3)	Moisture Content (%) [(W2-W3)/(W2-W1)] x 100
S1	5.00	500.00	300.00	40.40 %
S2	5.00	500.00	430.00	14.14 %
S3	5.00	500.00	400.00	20.20 %
S4	5.00	500.00	390.00	22.22 %
S5	5.00	500.00	410.00	18.18 %

Below are the results of the germination and plant growth of the padi huma bakilong.

Table 5: Germination and Mortality Rate of the Plants in the Soil Samples

Soil Sample	Number of seeds planted	Number of seeds germinated	Rate of germination (%)	Rate of mortality (%)
S1	54	0	0	100
S2	54	33	61.111	38.889
S3	54	31	57.407	42.592
S4	54	54	100	0
S5	54	20	37.037	62.962

Figure 1: Rate of Germination and Rate of Mortality

Table 6: Heights of the Plants in the Soil Sample After 4 Weeks

Soil Sample	Week 1 average height (cm)	Week 2 average height (cm)	Week 3 average height (cm)	Week 4 average height (cm)	Average height for four weeks (cm)
S1	0	0	0	0	0
S2	0	21.833	23.000	24.367	23.067
S3	0	8.633	16.833	24.300	16.589
S4	0	13.000	27.000	38.733	26.244
S5	0	0	8.200	9.167	5.789

Figure 2: Growth Rate of the Soil Samples

From Tables 5 and 6 and Figures 1 and 2, soil sample S4 has the most fertile soil as the plants grew with an average growth height of 26.244 cm per week and had a 100% germination rate. A combination of good soil texture (loam), good pH range (pH 6.39), high moisture content (22.22%) and abundance of nutrients led to the plants in the soil sample to grow better than the other five soil. Soil sample S2 had the second highest average growth height at 23.067 cm per week with a germination rate of 61.111% despite having a sandy soil texture and a moisture content of 14.14%. The abundance of nutrients may have contributed to this results. Soil sample S3 had an average growth height of 16.589 cm per week and a germination rate of 57.407%. Despite its highly acidic soil and comparatively lower abundance of nutrients compared to S2 and S4, the plants in S3 managed to grow with results similar to S2. S5 has the lowest average growth height with 5.789 cm per week and a germination rate of 37.037%. Furthermore, the seeds in this soil sample only germinated in week 3 after constant watering. Soil sample S1 is without a doubt the least fertile of the five soil samples, as no seeds germinated throughout the duration of the mini project.